The present invention relates generally to distributed computer systems, and more particularly, to a logon system and method for use with distributed and networked computer systems.
The prior art relating to controlling user access in a distributed processing environment is to request users to separately log on to each computer that provides needed services. This practice has many drawbacks. The user must remember many passwords, if passwords are different on each computer. Passwords transmitted in the clear (without security) may easily picked up by others. Repeated logon requests are inconvenient to the user. The use of a bypass scheme by the user to speed up the process could also increase the security risk to the system.
More specifically, in a distributed processing environment, a user must repeatedly provide user identification (ID) codes and passwords to gain access to various services located throughout the system. For instance, a user must log on to a workstation, then log on to new computers when new services are needed. The repetition of these logon sequences is very inconvenient for users. Moreover, if user passwords are not the same on all computers in the system, users must remember many different passwords. To reduce the possibility of using a wrong password, the user might write them down (perhaps posted somewhere close to the workstation). This is not a secure practice. In addition, a user who is in a hurry to obtain information from a particular resource may not wish to go through the repeated logon process. He or she may find ways to bypass the security procedures used in the system, which creates a system weakness. Another weakness is that, to logon remotely, the user ID code and password must be transmitted to the remote computer. Without a secure path from the user's workstation to the remote computer, anyone having access to the system could use a network analyzer to discover the password of the user.
Legion Technologies Corporation has a logon product known a TPX. The TPX product is a IBM mainframe product for a processing environment known as MVS/VM. It provides automated logon to MVS sessions, after an initial authentication to the end system. The user contacts the host computer and is authenticated. The host computer contains an access list of users and services, and grants access based on this list. Only the host computer needs to be modified and failures are localized to one host computer. However, this implementation is a homogeneous solution, with very limited communications available between IBM host servers (TELNET 3270). It is also a relatively expensive architecture to implement.
Another approach is known as the Kerberos system. In this system, a Kerberos server is provided and the user and an application on the host computer authenticate themselves to the server. The user software requests an authentication token from the host application, and both the hosts and user authentication tokens are sent to the server. The server responds with a token only readable by the user and host computer. The contents of the token is used to protect the data throughout the duration of the connection. This system provides for authentication at the application level, and provides for key distribution mechanism. However, this system requires a host server application modification. The server makes possible a single point failure mode. Also, a large initial transaction time is required.
It is therefore an objective of the present invention to provide a safe and user-transparent method and means for authenticating users in a distributed computing system that does not require special purpose hardware development.